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WORK PLAN FOR LIMITED SITE INVESTIGATION Irerracon Premium California Orchards, Tracy, California January 8, 2021 Terracon Project No. NA207103 Investigation and sample collection procedures will be conducted in accordance with Terracon's standard practices. The samples will be packaged for transport and submittal, under chain-of- custody procedures, to a State-of-California certified laboratory for analysis on a standard (5 to 7 business days) turnaround time (TAT). 2.6.1 Soil Borings No later than 48 hours prior to the start of field work, Terracon will notify SJCEHD of our proposed workday and confirm that a representative of the SJCEHD will be available for a backfilling inspection. Soil Borings Advancement and Soil Sampling A total of six (6) soil borings (SBs)will be advanced on the site including; five (5) soil borings to be advanced to a depth of approximately 15 feet below grade surface (bgs) for the collection of soil samples and one soil boring to be advanced to a depth of approximately 50 feet bgs, five feet into the first encounter of groundwater, or refusal, whichever occurs first. Refer to Exhibit 2 for the proposed boring locations. The proposed locations may be modified in the field to account for utility clearance, access limitations, and/or site conditions. Drilling services for the proposed soil borings will be performed by a State-of-California C-57 licensed driller using a truck- or track-mounted direct-push technology (DPT) drill rig under the supervision of a Terracon environmental professional and the oversight of a Terracon licensed Professional Geologist (P.G.). Soil samples will be collected continuously using single-use acetate liners to document lithology, color and relative moisture content. In addition, the samples will be field screened using sensory methods and a photoionization detector (PID) to detect the presence of total organic vapors. Drilling and sampling equipment will be cleaned using an Alconox° wash and potable water rinse prior to the beginning of the project and before collecting each soil sample. Two soil samples will be collected from each boring and submitted for laboratory analysis. The soil samples submitted for laboratory analysis will be collected from the zones exhibiting the highest volatile vapor readings or the interval of most-likely environmental impact as determined in the field by the sampling professional, such as the capillary fringe zone (if applicable), the intervals exhibiting a change in lithology, and/or from the bottom of the boring. Additional soil samples may be selected for delivery to the analytical laboratory. However, these soil samples will be placed on hold for potential contingent analyses, if recommended based on review of the initial soil sample analytical results. Responsive■ Resourceful ■ Reliable 4